Solar Panels for Batteries

[GBGochColorado]

Hello All,
Just purchased 2 Trojan T 105 6 volt batteries.

Question is, what size or wattage is recommended to keep the batteries topped off?

New at all this battery and solar stuff.

I also have 2 RV rated deep cycle batteries too, to use for my cpap. Or for back up.

Thank You in advance for any and all answers

Greg

[Canonman]

Depends on how much amp draw you'd have in a given period of time.
We don't use CPAP but our 200w Zamp portable keep our batteries topped off just fine after an evenings use including the furnace.
200w is about the max size for portable units due to weight.
More panels = more amps you can push into your batteries but more than two panels and they are too cumbersome to handle and so are typically permanently mounted on the roof of the TT.

[GHen]

I have 100 watt solar mounted on roof, I need to upgrade to 200 watt.